An organic light emitting diode (PLED) display device is self-luminous, simple in structure and ultra-thin, with fast response, a wide viewing angle, low power consumption and other characteristics. Therefore, it has become one of the important developing trends of a new generation of display devices and has gained more and more attentions.
The OLED display device emits light through a current-driven luminescent material, typically including an anode layer, an organic layer (or a functional layer), and a cathode layer. The organic layer includes a hole transport layer, a light emitting layer and an electron transport layer. When a voltage is applied across the anode electrode and the cathode electrode, electrons and holes are injected from the cathode electrode and the anode electrode into the electron transport layer and the hole transport layer, respectively, and then transfer to the light emitting layer via the electron transport layer and the hole transport layer. The electrons and holes are recombined in the light emitting layer to realize the self-luminous characteristics of the OLED.